Gradual depletion of fossil fuel resources, poor energy eiciency of conventional power plants, and environmental pollution have led to a new grid architecture known as smart microgrid. The smart microgrid concept provides a promising solution that enables high penetration of distributed generation from renewable energy sources without requiring to redesign the distribution system, which results in stable operation during faults and disturbances. However, distributed generators/loads and interaction between all nodes within a microgrid will substantially increase the complexity of the power system operation, control, and communications. Many innovative techniques and technologies have been proposed to address the complexity and challenges of microgrids including power quality, power low balancing, real-time power management, voltage and frequency control, load sharing during islanding, protection, stability, reliability, eiciency, and economical operation. All key issues of the microgrids, diferent solutions, and available methods and technologies to address such issues are reviewed in this chapter. Pros and cons of each method are discussed. Furthermore, an extensive comprehensive review for researchers and scholars working on microgrid applications is provided in this chapter to help them identify the areas that need improvements and innovative solutions for increasing the eiciency of modern power distribution grid.Keywords: AC microgrid, DC microgrid, microgrid power quality, power management, microgrid modeling, power electronics, renewable energies © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
IntroductionThe smart microgrid concept was irst developed in Refs. [1,2]. The capability of integration of a large number of distributed power generation sources and high penetration of renewable sources such as photovoltaic panels, wind turbines, and fuel cells within a smart microgrid made it very atractive. In fact, management of multiple distributed power generation sources including renewable energy sources in a smart microgrid ofers many advantages such as signiicant reduction in the need for a transmission and high voltage distribution system, satisfying the growing demand of electricity, and improving energy utilization eiciency and reliability. However, interaction between all nodes within a microgrid including both conventional and renewable energy generation sources will not only increase the complexity of the power system considerably, but it will also raise challenging issues of reliability and power quality due to intermitent nature of renewable sources. Therefore, many technical challenges must yet be overcome to ensure safe, secure, reliable, optimized, eicient, and cost efective operation of the microgrid.Academic scholars and industry experts ofe...